1. Field of the Invention
The present invention relates to a method of producing elongate articles having high dimensional stability and low thermal expansion, such as length measuring tools, particularly final or calibrating gauges, calipers or testing or sensing members, by using hollow cylinders made of composite fiber materials and fibers which have a negative coefficient of thermal expansion. The invention also relates to the elongate articles so produced.
2. Description of the Related Art
An elongate article in the form of a length measuring tool is described in German Patent Document No. 3,135,585. The article disclosed therein is composed of a ceramic or fiber reinforced material, such as carbon fiber and glass fiber reinforced plastics. It is further disclosed that the different types of carbon fibers used have either a small positive or a small negative coefficient of thermal expansion while the glass fibers used have a comparatively high positive coefficient of thermal expansion, and that measuring tools made of these materials are dimensionally stable and subject to only slight thermal expansion.